1. Field of the Invention
The present invention relates to an electronic component including a multilayer ceramic capacitor, and an interposer used when mounting the multilayer ceramic capacitor onto a circuit board.
2. Description of the Related Art
Currently, chip components, in particular, miniature multilayer ceramic capacitors are frequently used for mobile terminals such as cellular phones. A multilayer ceramic capacitor includes a rectangular component body that functions as a capacitor, and outer electrodes formed at opposite ends of the component body.
In related art, generally, as disclosed in Japanese Unexamined Patent Application Publication No. 8-55752, a multilayer ceramic capacitor is electrically and physically connected to a circuit board by placing outer electrodes directly on the mounting land of the circuit board of a mobile terminal, and bonding the mounting land and the outer electrodes together with a bonding agent such as a solder.
However, a multilayer ceramic capacitor is subject to mechanical distortion in some cases due to variations in the voltage applied to the multilayer ceramic capacitor. When this distortion occurs, the distortion is transmitted to the circuit board, causing the circuit board to vibrate. When the circuit board vibrates, vibration sound audible to the human ears occurs in some cases.
As a solution to this problem, for example, Japanese Unexamined Patent Application Publication No. 2004-134430 describes a configuration in which the multilayer ceramic capacitor is not directly mounted on the mounting land. In Japanese Unexamined Patent Application Publication No. 2004-134430, an interposer formed by an insulating substrate is used. In a case where an interposer is used, the multilayer ceramic capacitor is bonded to upper electrodes of the interposer, and lower electrodes of the interposer are bonded to mounting electrodes of the circuit board. The electrical continuity between each of the upper and lower electrodes is provided by a via-hole that penetrates the interposer.
However, Japanese Unexamined Patent Application Publication No. 2004-134430 adopts a special structure in which the arrangement direction of the lower electrodes and the arrangement direction of the upper electrodes in the interposer cross each other, that is, the arrangement direction of the outer electrodes of the multilayer ceramic capacitor and the arrangement direction of the mounting electrodes with respect to the circuit board of the interposer cross each other. Therefore, in a case where the multilayer ceramic capacitor is directly mounted onto the circuit board and vibration sound occurs, when an interposer is used as in Japanese Unexamined Patent Application Publication No. 2004-134430, changes to the land pattern or the like are required. However, such changes to the land pattern are difficult to achieve for circuit boards currently used which typically require high-density mounting. Accordingly, it is desired to allow easier structural design and mounting.
The present inventor has discovered that the solder applied when bonding the interposer to the circuit board climbs and wets onto the multilayer ceramic capacitor, and vibration of the multilayer ceramic capacitor is transmitted to the circuit board via the solder, thus compounding the problem caused by vibration of the multilayer ceramic capacitor. Accordingly, the present inventor has discovered a configuration that reduces the amount of applied solder that climbs and wets onto the multilayer ceramic capacitor to reduce transmission of vibration to the circuit board.